DESCRIPTION: (Adapted from applicant's description) Becoming literate is a multifaceted skill that all children must accomplish. Literacy becomes more complex for Spanish speaking children because they begin the literacy process with varied language experiences. Children may be raised in a home in which Spanish is the only language spoken and may become bilingual sequentially when they enter an educational setting. Others learn both languages simultaneously. Literacy development may be further complicated by differences between the home and school environments. This prospective longitudinal study addresses three interrelated questions: (a) What are the differences in the rate and quality of language and literacy development between children learning Spanish and English sequentially and simultaneously? (b) What factors of oral language development and the environment result in positive and negative literacy outcomes in bilingual children? and (c) How do the specific characteristics of bilingual children's linguistic systems relate to literacy outcomes and how does the home environment buffer children against negative outcomes? To address these questions, this study examines the language acquisition, literacy development, and home environment of 100 children of Puerto Rican descent who attend Head Start. Fifty children acquiring Spanish and English sequentially and 50 acquiring the two languages simultaneously will be studied from the ages of four to six years. The development of a subset of 24 children will be studied in depth. The results of the investigation will inform us of (a) the patterns of bilingual language acquisition that result in better literacy abilities; and (b) specific factors that should be targeted in interventions to facilitate better outcomes.